Dry ice kief is a loose cannabis concentrate collected by passing chilled, resin-bearing plant material over a mesh screen. The guide explores the bucket-and-bag technique and a homemade tumbler variation.
See how the screens work, what the micron numbers mean, and how this approach relates to traditional hash-making and cannabis oils.
The method / dry ice screening
What happens at the screen?
Cold and movement help resin-bearing trichomes separate from dried plant material. A mesh screen allows smaller particles to pass through while retaining larger material.
The video below shows the bucket-and-bag setup, how the mesh fits over the bucket, and the collection surface.
Using Bubble Bags for Dry Ice Kief
The bucket-and-bag setup pairs a mesh bag with dry ice and dried plant material for mechanical screening.
Simply take a few ounces of dried clippings and leaves and put them into a Bubble Bag Extraction Kit
Dry ice requires cold-rated protective gear and adequate ventilation. It also must never be sealed in an airtight container.
Now take a 220 micron bubble bag(paid link)
Now shake the bucket for a minute, then turn upside down and shake steady for a few minutes over a large, flat, clean area. Continue shaking until no more dust "kief" comes out from the screened end of the bubble bag. You can now throw away the dry ice and plant material that is in the bucket.
The screened material can be gathered from a clean work surface.
Compare the techniques
Dry-ice screening and ice-water hash
Dry-ice kief
Uses low temperatures and mechanical screening without immersing the plant material in water.
Ice-water hash
Uses cold water, agitation and filtration to collect resin-bearing particles. See the water hash guide for this separate method.
How do mesh sizes compare? A micron is one-thousandth of a millimeter. Different screen openings change the range of particles passing through. Explore more vocabulary in the cannabis glossary.
Dry Ice Kief Tumbler Extraction
Using a custom made kief tumbler, you can extract very large amounts of kief with ease. I built a large custom kief tumbler that runs on a bbq rotisserie motor and has Nylon 6/6 (paid link)Mesh 10 Micron Opening 28 Micron(paid link)
Following the same method as above in the "bubble bag" method, you can extract kief using a kief tumbler. Simply add the clippings and dry ice to the basket, close it, connect drill, spin for a few minutes over a large, clean flat surface. Once the kief or "dust" stops falling out of the screen, its done and you can trash the clippings and dry ice. The motorized tumbler is a second setup for handling larger batches of dried plant material.